The Cochrane Collaboration: Evidence-Based Medicine and Common Sense

Late in 2004, the Chesapeake Bay Society of Colon and Rectal Surgeons had a dinner meeting which my wife and I attended. After eating, we were privileged to hear from our honored guest speaker, Dr. Herand Abcarian, who gave a particularly thought-provoking talk. He prefaced his remarks by saying that he did not necessarily use all the information he was to give us, but he wished to challenge us, and get us thinking about what we do, and why we do it. He wished to be provocative. He talked about some of the traditional teachings of surgery, and then presented data, vetted by the Cochrane Collaboration, that illustrated that some of our time-honored traditions are just not true. For instance, “everybody gets an NG tube” was something I learned as an intern, even for gallbladder surgery. Nowadays, almost nobody gets an NG tube, and patients usually seem to do quite nicely without one. The Cochrane Collaboration has solid data that show no benefit for the routine use of NG tubes. Other similar examples were given, all fairly routine, all quite acceptable, until Dr. Abcarian mentioned routine repair of civilian colon injuries without colostomy. That topic is of interest to me, as a military surgeon, because we are seeing some attempts at colon repairs that are being done for severe injuries in Iraq. And when these repairs fail, patients are not doing well. Some of our National Guard and Reserves colleagues who are in Iraq are forgetting that war injuries are sometimes best treated with diversion, rather than repair. They are taking civilian teachings and habits to war, and the results are not always positive. So Dr. Abcarian had my attention as he discussed the proper treatment of colon injuries.

But then came the category that really caused me to wonder. Dr. Abcarian began discussing the data about bowel preps. As it turns out, there are no data to support the use of bowel preps before surgery. Patients do just as well without bowel preps. Their incidence of infection is no higher. Their anastomoses hold together just as well. The data are very clear-bowel preps are not needed. The routine use of mechanical bowel preparation in elective colorectal surgery was not shown to be of benefit. We had a vigorous discussion about these findings. I was amazed that several younger colorectal surgeons in the audience seemed to believe that bowel preps were actually harmful to the patient, and might be worse than nothing. Some more seasoned surgeons questioned the data and recalled the days prior to the emphasis on bowel preps, and the extremely high incidence of postoperative infections that occurred back then. I left wondering how anyone with any sense at all could accept such rubbish as this particular study.

Back in North Ogden, Utah, where I grew up, there is a quality that the old ranchers and farmers used to call “common sense,” which was highly regarded and ought not to be overlooked. These hard-working folks would wear warm clothing in the wintertime, try to stay out of the hot summer sun, avoid walking in the corral where the bull was kept. They did not need much scientific evidence to guide their lives. It was “common sense” to have those sorts of habits. And one of the most carefully followed bits of common sense was what one did around fecal matter. One did not labor in fecal matter if it could be avoided. One avoided contact with it. One washed carefully if soiled by it. And did not track it into the home. And tried very hard not to smell of it, or have it on clothes, or shoes. It was just not accepted as a desirable substance. These common-sense rules of conduct are not new, but have been around for hundreds of years. We know from ancient writings that stool was thought to be undesirable, and was to be avoided. If given the choice today, most of us would choose to work in a stool-free environment. Most of us find stool to be smelly, messy, in-the-way. Most of us have little positive to say about it. Most are repelled by it. There are important public health reasons that teach us to avoid stool.

Thus it is surprising to me to find that anyone would even study the proposition that elective colon surgery might be done without a bowel prep. The whole notion flies in the face of common sense. The question is not so much whether the patient will be helped (although I would argue that having a clean colon makes for a more comfortable convalescence postoperatively). In the absence of data that show that bowel preps are harmful to patients, the bigger question, in my mind, is a more selfish one. What kind of a workplace do I desire? What kind of a reputation would I like for my specialty, and my society? Will going without bowel preps really promote the fine art and science of colorectal surgery? Will excitement be generated when the word gets out that we no longer prefer to work in a clean place? Will the best and the brightest be attracted to a specialty that now delights in coming into contact with stool, manipulating stool, milking it around the bowel, cleaning it up when it spills, etc., etc., etc.? And when the accountants from the HMOs begin to read the good news that bowel preps are no longer needed, will we not save millions of dollars by forging on without them? Frankly, I cannot think of a worse message to send out.

I, like Dr. Abcarian, do not turn and run at the first sight of stool. When an incomplete prep has been done, I usually proceed none-the-less. However, I always enjoy surgery more in a clean, sweet-smelling environment. I prefer to be stool-free and proud.

I would also say this to those brilliant scientists and statisticians associated with Cochrane: “Pick your questions more wisely. You violated a basic common-sense principle when you became Defenders of Stool. You risk making all in your organization smell funny.” If this sort of study is what evidence-based medicine is all about, I believe that we will all be fully entertained for some years to come. And, by the way, I suppose we can look forward to the good news that we need not wear gloves when doing rectal exams. Surely, when that study is done, it will show that patients do just as well when we do not wear gloves. And all the farmers and ranchers of North Ogden, Utah, will be laughing when they hear the latest from Those Who Lack Common Sense.